Moldboard support assemblies of the type wherein the moldboard support frame is pivotally connected to one end of a vehicle supported drive frame for pivotal movement about a vertical axis are known, as evidenced by U.S. Pat. No. 3,464,129 to Bogenschutz, dated Sept. 2, 1969; and U.S. Pat. No. 3,604,131 to Bogenschutz, dated Sept. 14, 1971. The pivotal movement of the moldboard support frame about the vertical axis is accomplished by a motor driven worm gear, carried by the drive frame, intermeshing with a gear segment connected to the moldboard support frame. In order to maintain the drive frame and moldboard support frame in proper alignment, a suitable guide is provided between the frames. The guide is provided in Bogenschutz, U.S. Pat. No. 3,464,129, by a guide member connected to the moldboard support frame and slidably mounted in a slot formed in a guide block connected to the drive frame.
While Bogenschutz's guide arrangement is satisfactory for its intended purpose, it is subject to certain objections, particularly the expense incurred in fabricating the various components to make up the guide arrangement. After considerable research and experimentation, the guide arrangement of the present invention has been devised which is considered an improvement on Bogenschutz's guide arrangement, and comprises, essentially, a pair of bearing blocks or wear pads mounted on the drive frame and engaging the bottom surface of a frame component in the moldboard support frame. Another wear pad is connected to the worm gear support brackets and engages the top surface of the gear segment. By this construction and arrangement, the wear pads forming the guide arrangement are connected to the drive frame only, whereby conventional moldboard support frames having gear segments are readily attachable to the drive frame of the present invention and are properly guided thereby. Furthermore, the worm gear support brackets perform the dual function of not only supporting the worm gear but also support the wear pad engaging the top surface of the gear segment.